参考AD公司的C/C++ Compiler and Library Manual for Blackfin® Processors

cfft
           N-point radix-2 complex input FFT
Synopsis
            #include <filter.h>
void cfft_fr16(const complex_fract16 input[],
                        complex_fract16 output[],
                        const complex_fract16 twiddle_table[],
                        int twiddle_stride,
                        int fft_size,
                        int *block_exponent,
                        int scale_method);
void cfft_fr32(const complex_fract32 input[],
                         complex_fract32 output[],
                         const complex_fract32 twiddle_table[],
                         int twiddle_stride,
                         int fft_size,
                         int *block_exponent,
                         int scale_method);
Description
The cfft functions transform the time domain complex input signal
sequence to the frequency domain by using the radix-2 Fast Fourier
Transform (FFT).
The size of the input array input and the output array output is fft_size,
where fft_size represents the number of points in the FFT. By allocating
these arrays in different memory banks, any potential data bank collisions
are avoided, thus improving run-time performance. If the input data can
be overwritten, optimal memory usage can be achieved by also specifying
the input array as the output array.

非常感谢！！！